Lunenburg, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.6 °C (low) to 11.7 °C (high). Annual precipitation averages 1020.6 Millimeters. Lunenburg is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.1 °C | -3.5 °C | 57.66 mm |
| February | -14.4 °C | -1.6 °C | 54.86 mm |
| March | -8.8 °C | 3.4 °C | 55.12 mm |
| April | -1.8 °C | 10.8 °C | 78.49 mm |
| May | 4.7 °C | 18.6 °C | 98.04 mm |
| June | 9.8 °C | 23.1 °C | 107.95 mm |
| July | 12.4 °C | 25.6 °C | 106.68 mm |
| August | 11.3 °C | 24.7 °C | 105.66 mm |
| September | 7.1 °C | 20.7 °C | 92.46 mm |
| October | 1.4 °C | 13.1 °C | 104.65 mm |
| November | -4 °C | 5.8 °C | 74.17 mm |
| December | -10.4 °C | -0.6 °C | 84.84 mm |
| Annual | -0.6 °C | 11.7 °C | 1020.58 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |